Method for producing a composite pane

Abstract

The invention relates to a method for producing a composite pane (100), having the steps of: - providing a pre-composite (101), containing a first glass pane (1) with a first surface (I) and a second surface (II) and a second glass pane (2) with a third surface (III) and a fourth surface (IV), wherein the first glass pane (1) is connected to the second glass pane (2) via a peripheral edge seal (6) which is provided with at least one pre-composite inlet opening (8) and at least one pre-composite outlet opening (9), the first surface (I) and the fourth surface (IV) face away from each other and form the outer surfaces (13) of the pre-composite (101), and the second surface (II) and the third surface (III) face one another and form the inner surfaces (14) of the pre-composite, a pane intermediate space (12) being formed between the two glass panes (1, 2) and the edge seal (6), - filling an optically clear liquid adhesive (5) into the pane intermediate space (12), wherein a hydrostatic pressure of the optically clear liquid adhesive (5), said pressure acting on the inner surfaces (14) in the form of an internal pressure, is counteracted by an external pressure which acts on the outer surfaces (13) and is exerted by pressure surfaces (23) of pressure pads (17) that lie flatly against the outer surfaces (13), and the external pressure is based on the hydrostatic pressure of fluid (24) in the pressing pads (17), and - curing the optically clear liquid adhesive (5) while maintaining the external pressure on the outer surfaces (13), thus producing the composite pane (100).

Description

[0001] Process for producing a composite pane

[0002] The invention lies in the technical field of industrial pane production and relates to a method for producing a composite pane.

[0003] Laminated panes typically consist of two glass panes and an intermediate layer, which firmly bonds (laminates) the two panes. The intermediate layer is typically made from one or more thermoplastic films, particularly PVB films. Furthermore, it is known that laminated panes can be equipped with electrical functional elements embedded in the intermediate layer. Thermoplastic films are used to embed such a functional element, positioned above and below the functional element. Furthermore, the functional element can be embedded in the cutout of another thermoplastic film, which surrounds the functional element like a passe-partout, to protect it from excessive mechanical stress during the lamination of the laminated pane.Composite panes with integrated functional elements are particularly common in vehicle windows, for example, windshields or roof windows. Composite panes of this type are known, for example, from WO2014029536A1, WO2014086555A1, or WO2017157626A1.

[0004] Laminated glass panes are typically manufactured by autoclaving, where the glass panes are laminated together over thermoplastic films at high temperatures and high pressure. These conditions place significant stress on the glass panes, especially on the often sensitive electrical components. Stresses can cause optical distortions in the glass panes, and integrated functional elements can even be damaged.

[0005] GB 1101202 A and FR 1412330 A disclose a process in which a transparent resin is poured into the space between panes. The panes are placed in a container that is filled with a liquid at the same time as the resin is poured in.

[0006] In contrast, the object of the present invention is to provide an improved method for producing composite panes with high optical quality and low waste. In particular, composite panes with integrated electrical functional elements should be producible with high optical quality, whereby the electrical functional elements should not be exposed to critical stress during the production of the composite panes. Furthermore, the method should be feasible using production equipment commonly used in the industrial series production of composite panes, allowing for the simple, cost-effective, and reliable production of composite panes with high optical quality and low waste in large quantities.

[0007] These and other objects are achieved according to the invention by a method for producing a composite pane according to the independent patent claim. Advantageous embodiments of the invention are set forth in the subclaims.

[0008] According to the invention, a method for producing a laminated pane, more precisely a laminated glass pane, is shown. The laminated pane advantageously has at least one integrated electrical functional element, wherein the electrical functional element is integrated into the laminated pane, i.e., it is located between the two individual panes of the laminated pane.

[0009] The process for producing a composite pane comprises the following steps, which are carried out, for example, in the order given according to alphabetical designation:

[0010] Step a)

[0011] First, a pre-laminate is provided. The pre-laminate contains a first glass pane and a second glass pane, the first glass pane being connected to the second glass pane via a circumferential edge seal provided with at least one inlet opening and at least one outlet opening. The first glass pane has a first surface and a second surface. The second glass pane has a third surface and a fourth surface. In the pre-laminate, in which the two glass panes are connected to one another, the first surface of the first glass pane and the fourth surface of the second glass pane face away from one another and form the two outer surfaces of the pre-laminate, while the second surface of the first glass pane and the third surface of the second glass pane face towards one another and form the two inner surfaces of the pre-laminate.

[0012] The glass panes each have two surfaces (main surfaces) intended for viewing and arranged essentially parallel to one another, as well as a side edge surface extending therebetween. The main surfaces of the glass panes form the outer and inner surfaces of the pre-laminated glass, respectively. A cavity is formed in the pre-laminated glass between the second surface of the first glass pane, the third surface of the second glass pane, and the edge seal, which cavity is referred to below as the "pane gap" for ease of reference. The pre-laminated glass pane is arranged in particular non-horizontally, preferably vertically (essentially vertically), with the first glass pane and the second glass pane being arranged vertically.

[0013] Step b)

[0014] A liquid, optically clear adhesive is then poured into the cavity between the panes. This occurs through at least one inlet opening. Air can escape from the cavity through at least one outlet opening, allowing the cavity to be completely filled with the liquid, optically clear adhesive. It is also possible for liquid, optically clear adhesive to be removed from the cavity via the outlet opening. For ease of reference, the inlet opening is hereinafter referred to as the "pre-bond inlet opening" and the outlet opening as the "pre-bond outlet opening."

[0015] The hydrostatic pressure of the liquid, optically clear adhesive in the cavity between the panes (liquid column) exerts pressure on the two inner surfaces of the pre-laminated glass, hereinafter referred to as "internal pressure" for ease of reference. The hydrostatic pressure can be caused solely by gravity, but it is also possible that the hydrostatic pressure in the liquid, optically clear adhesive is increased by additional external pressure. Preferably, the hydrostatic pressure of the liquid, optically clear adhesive is caused solely by gravity.

[0016] During the filling of the liquid, optically clear adhesive into the cavity between the panes, i.e., simultaneously with this, the internal pressure caused by the hydrostatic pressure on the two inner surfaces of the pre-laminated glass is counteracted by a pressure acting on the two outer surfaces of the pre-laminated glass, hereinafter referred to as "external pressure" for ease of reference. The external pressure is exerted by the pressure surfaces of two or more pressure pads, which bear flat against the outer surfaces of the pre-laminated glass. The pressure pads, or the pressure surfaces of the pressure pads, are arranged on either side of the pre-laminated glass. Thus, the pressure surfaces of the pressure pads can act on the outer surfaces of the pre-laminated glass from two sides. The external pressure acting on the outer surfaces of the pre-laminated glass is based on the hydrostatic pressure of fluid in the pressure pads.The hydrostatic pressure in the pressure cushions can be generated solely by gravity, but it is also possible that the hydrostatic pressure is increased by additional external pressure. Preferably, the hydrostatic pressure of the fluid is determined solely by gravity.

[0017] The pressure pads are designed to be flexible and, for this purpose, each comprise a flexible pad cover (e.g., made of a flexible film made of a polymer material). The pad cover defines a cavity, hereinafter referred to as the "pad cavity" for ease of reference, which can be filled with a fluid. Depending on the process, the pressure pads are first filled with fluid during the filling of a liquid, optically clear adhesive or are already at least partially, or in particular completely, filled with fluid.

[0018] At least during the filling of the cavity between the panes with a liquid, optically clear adhesive, the pressure pads are positioned adjacent to the outer surfaces of the pre-laminated composite. During the filling of the cavity between the panes with a liquid, optically clear adhesive, the fluid in the pressure pads exerts an external pressure on the two outer surfaces of the pre-laminated composite via the pressure surfaces that are in direct contact with the two outer surfaces of the pre-laminated composite, based on the fluid's hydrostatic pressure.

[0019] For the purposes of the invention, the term "pressure surface" refers to an area of ​​the cushion cover intended to bear flatly against an adjacent outer surface of the pre-composite when the pressure cushion is filled with fluid. Thus, the pressure surfaces can also be considered sections of the cushion cover intended to bear against the outer surfaces.

[0020] The pre-assembly is or will be arranged between the pressure pads in such a way that the pressure pads, which are at least partially filled with fluid, are pressed in or deformed by the pre-assembly compared to a state without a pre-assembly arranged between them, so that the pressure surfaces can come into contact with the outer surfaces and the hydrostatic pressure of the fluid in the pressure pads acts as external pressure on the outer surfaces via the pressure surfaces (areas of the pad covers). The outer surfaces of the pre-assembly thus functionally take the place of the (adjacent) pressure surface and are subjected to the hydrostatic pressure of the fluid in the pressure pad. Preferably, the external pressure exerted by a pressure pad on the outer surfaces of the pre-assembly essentially corresponds to the hydrostatic pressure of the fluid in the pressure pad, although it is understood that the external pressure can also be (slightly) reduced compared to the hydrostatic pressure in the pressure pad.

[0021] Step c)

[0022] The liquid, optically clear adhesive is then cured while maintaining external pressure on the outer surfaces, creating the laminated pane. External pressure is therefore exerted on the outer surfaces of the pre-laminated pane not only while the cavity between the panes is being filled with a liquid, optically clear adhesive, but also while the liquid, optically clear adhesive is curing. In any case, external pressure is exerted on the outer surfaces of the pre-laminated pane until the liquid, optically clear adhesive has solidified to such an extent that hydrostatic pressure (internal pressure) no longer acts on the inner surfaces of the pre-laminated pane.

[0023] Step b) and step c) can be carried out one after the other, but also simultaneously if the curing of the liquid, optically clear adhesive already takes place during the filling process.

[0024] After the liquid, optically clear adhesive has cured, the external pressure can be released and the composite pane can be removed from the pressure pads.

[0025] When pouring the liquid, optically clear adhesive into the space between the panes, a fundamental problem arises that the column of liquid between the two glass panes exerts internal pressure on the glass panes due to hydrostatic pressure, which can cause them to deform (bulge outwards) or even break. Furthermore, the edge seal can be damaged. This is avoided with the method according to the invention by counteracting the internal pressure with the external pressure exerted by the pressure pads. Thus, the internal and external pressures oppose each other, so that the internal pressure is always reduced, which may be sufficient to prevent deformation or breakage of the glass panes. Preferably, the external pressure is dimensioned such that the pressures acting on the internal and external surfaces balance each other.Thus, the filling of the space between the panes with the liquid, optically clear adhesive takes place with a reduced mechanical load on the glass panes and preferably even without any significant mechanical load on the glass panes (compensation of the internal pressure by the external pressure), which is particularly advantageous.

[0026] If an integrated electrical functional element is provided, this can be advantageously protected from mechanical stress, since lamination of the glass panes does not occur at high temperatures and high pressures. Rather, in the composite pane produced by the method according to the invention, the intermediate layer is essentially made of an optically clear adhesive. This adhesive can be poured in liquid form into the space between the glass panes and then cured, thereby advantageously avoiding at least critical mechanical stress on the functional element.

[0027] In the context of the invention, the term "pressure" is understood, in accordance with the common understanding, to mean a force acting perpendicularly on a body and distributed over its area.

[0028] For the purposes of the invention, the term "fluid" is understood, in accordance with common understanding, to mean a non-solid, liquid, or gaseous substance. Preferably, this is a liquid substance that is filled into the pressure pads.

[0029] The term "flexible" in the context of the invention, in accordance with common understanding, is understood to mean a bendable or elastically deformable property. The respective cushion cover of the pressure cushion is flexible and can be pressed flat against an adjacent outer surface of the pre-assembled composite by filling the cushion cavity with fluid. The pressure surface is the area of ​​the cushion cover intended to be pressed against the outer surface. The degree of flexibility of the cushion covers can essentially be chosen arbitrarily, as long as contact with the pressure surface is possible. In other words, the cushion cover of a pressure cushion is sufficiently flexible if contact between the pressure surface (i.e., area of ​​the cushion cover) and an outer wall of the pre-assembled composite is possible due to the hydrostatic pressure of the fluid in the pressure cushion.

[0030] The terms "vertical" and "horizontal" refer to the direction of gravity, where "vertical" is parallel to the direction of gravity and "horizontal" is perpendicular to the direction of gravity.

[0031] Optically clear adhesives, usually abbreviated to OCA (Optically Clear Adhesive), are well known to those skilled in the art. This applies in particular to liquid, optically clear adhesives, usually abbreviated to LOCA (Liquid Optically Clear Adhesive), which are also commercially available and freely available from a variety of suppliers. Optically clear adhesives are characterized in particular by their high optical quality. They are primarily used where high optical quality is required, so that the adhesive layer is virtually invisible, for example in displays or touch panels. Therefore, optically clear adhesives are often used in touch-sensitive displays, for example to connect them to an LCD display or to connect plastic covers to touch-sensitive displays.Optically clear adhesives are particularly characterized by high light transmission and the fact that low-distortion visibility is possible.

[0032] In the method according to the invention, an optically clear adhesive in liquid form is used to fill the cavity between the panes. The liquid, optically clear adhesive can, in principle, be selected as desired, as long as it is sufficiently flowable to fill the cavity between the panes and curing is possible in the cavity between the panes. The liquid, optically clear adhesive can, for example, contain or consist of polyurethane (PU), polyacrylate, polyacetate resin, casting resin, or a copolymer or mixture thereof. The optically clear adhesive advantageously consists of a casting resin, in particular based on polyurethane or silicone.

[0033] The liquid, optically clear adhesive is curable, meaning it can be irreversibly cured. Typically, it is a plastic that is cured into a polymer-crosslinked state. This distinguishes the curable adhesive significantly from a thermoplastic, which, while also optically transparent, can always be softened (i.e., reversibly) by applying heat. In contrast, the cured, optically clear adhesive cannot be returned to a flowable state once it has cured. The optically clear adhesive is therefore not a thermoplastic.

[0034] Depending on the adhesive (LOCA) used, curing can occur through thermal curing (i.e., application of heat), through electromagnetic radiation, in particular UV radiation, IR radiation, or microwave radiation, through ultrasound, through the application of moisture, or through a chemical reaction between different components (in particular a two-component adhesive). Particularly when curing is based on a chemical reaction, the adhesive (LOCA) can already cure while the cavity between the panes is being filled. For example, in this case, the aforementioned steps b) and c) of the method according to the invention are carried out simultaneously, although the simultaneity of steps b) and c) can, in principle, also be provided for with a different curing mechanism for the adhesive (LOCA).

[0035] In one embodiment of the method according to the invention, the pre-laminate is arranged (essentially) vertically, i.e. with a (essentially) vertical arrangement of the two glass panes, between the flexible pressure pads, wherein the pressure pads are located on both sides of the pre-laminate, i.e. the pressure pads are arranged on both outer surfaces of the pre-laminate. The pressure pads are not yet filled with fluid or at least do not contain so much fluid that a pressure surface comes into contact with an outer surface. A small amount of fluid can therefore be present in the pressure pads, but this has no effect as long as no pressure surface exerts a mechanical force on the pre-laminate.

[0036] After positioning the pre-laminate between the pressure pads, the liquid, optically clear adhesive is poured into the space between the panes. Simultaneously with the pouring of the optically clear adhesive, fluid is poured into the pressure pads such that the internal pressure acting on the inner surfaces of the pre-laminate is counteracted by the external pressure acting on the outer surfaces of the pre-laminate. Preferably, the internal pressure is substantially compensated by the external pressure. In other words, the space between the panes is filled with the liquid, optically clear adhesive, and simultaneously the pressure pads are filled with fluid, such that the internal pressure on the inner surfaces caused by the hydrostatic pressure of the liquid, optically clear adhesive is counteracted by the external pressure on the outer surfaces caused by the hydrostatic pressure of the fluid.

[0037] The pressure pads are filled with fluid depending on or in accordance with the filling of the cavity between the panes with optically clear adhesive. Thus, while the cavity between the panes is continuously filled with a liquid, optically clear adhesive (LOCA), the pressure pads between which the pre-laminate is located are continuously filled with fluid. This is done in such a way that the growing hydrostatic pressure (internal pressure) generated by the rising LOCA column is preferably compensated as completely as possible by the growing hydrostatic pressure (external pressure) of the fluid in the pressure pads, or at least reduced. The higher the LCOA column rises in the cavity between the panes, the higher the fluid levels in the pressure pads also rise, so that the opposing pressures preferably always balance and compensate each other.This means that the space between the panes is filled essentially without mechanical stress on the glass panes and, if present, an integrated electrical functional element, which is particularly advantageous.

[0038] According to the above embodiment, the method for producing a composite pane comprises the following steps:

[0039] Providing a pre-laminate assembly comprising a first glass pane having a first surface and a second surface and a second glass pane having a third surface and a fourth surface, wherein the first glass pane is connected to the second glass pane via a circumferential edge seal provided with at least one inlet opening and at least one outlet opening, wherein the first surface and the fourth surface face away from each other and form the outer surfaces of the pre-laminate assembly, and the second surface and the third surface face each other and form the inner surfaces of the pre-laminate assembly, wherein a space between the panes is formed between the second surface, the third surface and the edge seal,

[0040] Arranging the pre-laminate with a substantially vertical arrangement of the two glass panes between at least two pressure pads,

[0041] Pouring a liquid, optically clear adhesive into the cavity between the panes and simultaneously pouring fluid into the pressure pads in such a way that a hydrostatic pressure of the liquid, optically clear adhesive acting on the inner surfaces of the pre-laminated structure is counteracted by an external pressure acting on the outer surfaces of the pre-laminated structure,

[0042] Curing of the liquid, optically clear adhesive while maintaining external pressure on the outer surfaces, creating the composite pane.

[0043] The hydrostatic pressure generated by gravity depends on the density of the liquid optically clear adhesive (LOCA) used or on the density of the fluid used. If the densities of the LOCA and the liquid fluid are at least approximately equal, it is advantageous to fill the LOCA into the cavity between the panes and the liquid fluid into the pressure pads in such a way that a surface of the LOCA and respective surfaces of the liquid fluid in the pressure pads are essentially at the same level at all times. The internal and external pressures then completely compensate each other. Preferably, the liquid fluid is selected accordingly and has a density that corresponds to or only slightly differs from the density of the LOCA. The "surface" of the LOCA or liquid fluid is understood to be the highest surface with respect to gravity, thus the surface of the LOCA or fluid that determines the level.

[0044] If the liquid fluid and LOCA have significantly different densities, the process can be adapted by adjusting the relative position of the surfaces of the liquid fluid and the LOCA column during the filling of the inter-pane space and the pressure pad to achieve the most complete compensation of internal and external pressure. This allows the LOCA level to be maintained a constant amount above or below the fluid surfaces during filling. Thus, the liquid, optically clear adhesive is filled into the inter-pane space and the liquid fluid is filled into the pressure pads in such a way that a surface of the optically clear adhesive and respective surfaces of the liquid fluid in the pressure pads are always at a constant distance (from each other) in the direction of gravity.

[0045] Although preferred, advantageous effects of the method according to the invention can also be achieved if there is no complete compensation of the internal pressure by the external pressure, whereby deviations from complete compensation of the pressures are acceptable as long as the internal pressure acting on the pre-composite is significantly reduced by the external pressure compared to filling in an air atmosphere. For example, even if LOCA and liquid fluid have the same density, slight deviations in the levels of fluid and LOCA column can be acceptable during filling with LOCA and fluid. In one process, there is no complete compensation of the internal pressure by the external pressure. In another process, the internal pressure is completely compensated by the external pressure.

[0046] In a further embodiment of the method according to the invention, the liquid, optically clear adhesive is poured into the space between the panes and at the same time the pre-laminate is inserted with the two glass panes arranged essentially vertically between the pressure pads located on either side of the pre-laminate, i.e. on both outer surfaces, the pressure pads already being at least partially, in particular completely, filled with fluid. The pre-laminate is inserted in such a way that the internal pressure acting on the inner surfaces of the pre-laminate is counteracted by the external pressure acting on the outer surfaces of the pre-laminate. In this method, the pressure pads are therefore already at least partially, preferably completely, filled with fluid, so that the pre-laminate is inserted between the fluid-filled pressure pads at the same time as it is filled with LOCA.When the pre-composite is inserted between the pressure pads, these are pressed in or deformed so that the hydrostatic pressure of the fluid in the pressure pads acts as external pressure on the outer surfaces of the pre-composite, i.e. the outer surfaces of the pre-composite are brought into contact with the pressure surfaces by the insertion.

[0047] Thus, while the space between the panes is continuously filled with LOCA, the pre-composite is continuously inserted between the pressure pads that are already at least partially, or in particular completely, filled with fluid. This is done in such a way that the increasing hydrostatic pressure (internal pressure) generated by the rising LOCA column is preferably compensated as completely as possible by the hydrostatic pressure (external pressure) of the fluid in the pressure pads or at least reduced.

[0048] With regard to the densities of LOCA and liquid fluid, as well as their levels, the statements regarding the above process apply analogously. Thus, if the density of LOCA and liquid fluid is at least approximately the same, the pre-composite is inserted between the pressure pads during filling of the liquid, optically clear adhesive in such a way that a surface of the LOCA and respective surfaces of the liquid fluid in the pressure pads are essentially at the same level at all times. Minor deviations from this are generally acceptable. If the densities of LOCA and liquid fluid differ significantly, it can be advantageous if the pre-composite is inserted between the pressure pads during filling of the LOCA in such a way that a surface of the LOCA and respective surfaces of the fluid in the pressure pads are at a constant distance (from each other) in the direction of gravity at all times.

[0049] According to the above embodiment, the method for producing a composite pane comprises the following steps:

[0050] Providing a pre-laminate assembly comprising a first glass pane having a first surface and a second surface and a second glass pane having a third surface and a fourth surface, wherein the first glass pane is connected to the second glass pane via a circumferential edge seal provided with at least one inlet opening and at least one outlet opening, wherein the first surface and the fourth surface face away from each other and form the outer surfaces of the pre-laminate assembly, and the second surface and the third surface face each other and form the inner surfaces of the pre-laminate assembly, wherein a space between the panes is formed between the second surface, the third surface and the edge seal,

[0051] Pouring a liquid, optically clear adhesive into the space between the panes and simultaneously inserting the pre-composite between at least two pressure pads filled at least partially, in particular completely, with fluid in such a way that an internal pressure acting on the inner surfaces of the pre-composite due to the hydrostatic pressure of the liquid, optically clear adhesive is counteracted by an external pressure acting on the outer surfaces of the pre-composite,

[0052] Curing of the optically clear adhesive while maintaining external pressure on the outer surfaces of the pre-composite, creating the composite pane.

[0053] As already explained, it is particularly advantageous if the internal pressure acting on the inner surfaces of the pre-composite is substantially compensated by the external pressure acting on the outer surfaces of the pre-composite. Depending on the densities of the LOCA and the liquid fluid, and possibly taking into account the flexibility of the pressure pads, the process can be carried out such that the levels of the LOCA and the liquid fluid are at least approximately equal, in particular exactly equal, or have a constant distance, as long as the LOCA has not yet cured.

[0054] The external pressure is exerted by two or more pressure pads arranged on either side of the pre-composite, i.e., on both outer surfaces. One or more pressure pads are provided on each outer surface. Advantageously, a single pressure pad is located on each outer surface, through which the external pressure is exerted on this outer surface of the pre-composite, i.e., exactly two pressure pads are provided on the pre-composite.

[0055] The pressure pads lie flat against the outer surfaces so that the internal pressure acting over the surface can be effectively counteracted by an external pressure acting over the surface, thus preventing bulging or deformation of the glass panes or glass breakage. This can sometimes be achieved even if the outer surfaces are not subjected to external pressure over their entire surface, when the space between the panes is completely filled with LOCA. At least when the space between the panes is completely filled with LOCA, the pressure pads or the pressure surfaces lie largely, preferably fully, against the outer surfaces of the pre-laminated glass, with advantageously more than 70%, in particular more than 90% and advantageously 100% of the outer surfaces being covered by the pressure surfaces applied by means of fluid pressure. The pressure surfaces and outer surfaces are advantageously the same size.The printing surfaces are advantageously of a size that corresponds at least to the size of the outer surfaces.

[0056] The pressure surfaces are advantageously adapted to the outer surfaces in size and shape, i.e. their size and shape are the same. When completely filled with fluid, the pressure pads preferably each have a substantially cuboid shape, with two surfaces (main surfaces) that are arranged substantially parallel to one another, and a side edge surface running between them. The main surfaces of the pressure pads opposite the outer surfaces are the pressure surfaces of the pressure pads. In this way, the pressure surfaces can be specifically adapted to the size and shape of the outer surfaces. The shape of the pressure pads can be formed in a simple manner, in particular by means of edge reinforcements. This is known to those skilled in the art, so it need not be discussed in detail here. The pressure pads can also have any other shape and size, depending on the shape and size of the composite pane.

[0057] It is understood that the pressure surfaces of the pressure pads are successively pressed against the respective outer surface as the pressure pads are increasingly filled with fluid, based on the hydrostatic pressure of the fluid. When the pre-assembly is inserted between the fluid-filled pressure pads, the pressure surfaces are successively pressed against the outer surfaces as the pre-assembly is inserted.

[0058] For example, exactly two pressure surfaces are in contact with the two outer surfaces of the pre-laminated glass with 100% coverage of the outer surfaces when the cavity between the panes is completely filled with LOCA.

[0059] In the method according to the invention, a pre-laminate is provided. The pre-laminate can be produced by connecting the first glass pane to the second glass pane via a circumferential edge seal provided with at least one pre-laminate inlet opening and at least one pre-laminate outlet opening to form a pre-laminate, wherein the space between the panes is formed. In the provided pre-laminate, the first glass pane and the second glass pane are connected to one another by the edge seal. If an integrated electrical functional element is provided, the electrical functional element can, according to one embodiment, be fastened to a surface of the first glass pane (i.e. to the second surface), wherein the surface of the first glass pane with the functional element faces the second glass pane and wherein the space between the panes is formed which contains the functional element.For this purpose, the electrical functional element can first be attached to a surface of the first glass pane using an adhesive. The adhesive can be, for example, a (double-sided) adhesive film, an adhesive (e.g. a hot melt adhesive or a polyurethane adhesive), or a butyl compound. The adhesive can only connect the functional element to the first glass pane at specific points. For example, adhesive dots can be applied in a distributed manner on a surface of the functional element (e.g. in a peripheral edge area of ​​the functional element) and the functional element can be adhered to the first glass pane using these adhesive dots. Alternatively, the adhesive can also bond the functional element to the first glass pane over its entire surface. For this purpose, one surface of the functional element can be completely coated with the adhesive, and the functional element can then be adhered to the first glass pane over its entire surface.The adhesive can also be a thermoplastic film. The functional element is then laminated to the first glass pane via the thermoplastic film. The thermoplastic film can cover the entire surface (main area) of the first glass pane, and the functional element is arranged on a portion of the thermoplastic film. The thermoplastic film can be based, for example, on polyvinyl butyral (PVB), ethylene-vinyl acetate (EVA), or thermoplastic polyurethane (TPU).

[0060] The first glass pane (optionally with attached functional element) is joined to the second glass pane to form a pre-laminate. This is achieved by means of a circumferential edge seal, which is arranged in an edge region, preferably directly adjacent to the side edge, between the first and second glass panes. The edge seal keeps the glass panes at a distance so that a cavity (i.e. the space between the panes) is formed between them, which is delimited by the glass panes and the edge seal. The space between the panes is to be filled with the liquid, optically clear adhesive. If a functional element is provided, the surface of the first glass pane provided with the functional element faces the second glass pane so that the functional element is located in the space between the panes.The edge seal can be formed, for example, from an adhesive film, a polyurethane adhesive, a butyl compound, polysulfide or other sealing materials.

[0061] The edge seal must be provided with at least one pre-bonded inlet opening through which the liquid, optically clear adhesive is filled, and at least one pre-bonded outlet opening, which serves to vent the space between the panes during filling with the liquid, optically clear adhesive. This can be achieved, for example, by using cannulas pushed through the edge seal or valves integrated into the edge seal. The pre-bonded inlet opening and the pre-bonded outlet opening can be created directly during the edge seal production process or subsequently.

[0062] It is understood that it is also possible to connect the functional element not only to the first glass pane using an adhesive, but also to the second glass pane using an adhesive.

[0063] The liquid, optically transparent adhesive is poured into the cavity between the panes via the pre-laminated glass filling opening. For this purpose, the pre-laminated glass filling opening is preferably provided with a flexible supply line, for example a plastic hose, through which the liquid, optically clear adhesive is supplied from a reservoir. While the cavity between the panes is being filled, the outer surfaces of the pre-laminated glass are gradually subjected to external pressure by the pressure surfaces of the pressure pads, which counteracts the internal pressure. The pre-laminated glass is preferably arranged (essentially) vertically, meaning that the first and second glass panes are aligned vertically.

[0064] In a preferred process, the pre-composite inlet opening is located at the bottom and the pre-composite outlet opening at the top, i.e., above the pre-composite inlet opening. This allows the liquid, optically clear adhesive to be filled without bubbles. However, the reverse arrangement is also conceivable, with the pre-composite inlet opening located at the top and the pre-composite outlet opening located at the bottom, or an arrangement in which the pre-composite inlet opening and the pre-composite outlet opening are positioned laterally.

[0065] Once the space between the panes is completely filled with the liquid, optically clear adhesive, the entire outer surfaces of the pre-laminated glass are advantageously subjected to external pressure in a corresponding manner, so that there is no area between the two glass panes that is not subjected to opposing pressures. The outer surfaces remain subjected to external pressure as long as the liquid, optically clear adhesive has not yet (fully) cured. During curing, the pre-laminated glass is transformed into the laminated glass, with the optically clear adhesive and, if necessary, other elements located between the glass panes forming the intermediate layer. Once the liquid, optically clear adhesive has cured, hydrostatic pressure (internal pressure) is no longer exerted. The external pressure can then be removed.

[0066] After filling the cavity between the panes with a liquid, optically clear adhesive, the pre-bonded inlet and outlet openings are sealed. This can be done before or after the liquid, optically clear adhesive has cured. If the openings are formed by cannulas, they can be pulled out of the edge seal or left in the composite pane. Valves can be removed or left in the composite pane. If cannulas or valves are removed, the remaining opening is preferably sealed with additional sealant. However, a seal can also be achieved with the cured, optically clear adhesive.

[0067] The time required for the liquid, optically clear adhesive to cure can be influenced by temperature in many curing processes. In particular, curing can be accelerated by applying heat. Conversely, curing can be slowed by cooling. The curing time can therefore be controlled, for example, by heating or cooling the liquid, optically clear adhesive.

[0068] If the liquid, optically clear adhesive begins curing immediately upon filling (as is the case with a two-component adhesive, for example), this can lead to uneven curing: the earlier a portion of the liquid, optically clear adhesive is poured into the cavity, the sooner it will fully cure. Uneven or delayed curing can manifest itself, particularly in reduced optical quality, and can also lead to mechanical stress during curing.

[0069] To avoid this and achieve the most uniform, simultaneous curing of the liquid, optically clear adhesive possible, multiple pressure pads can be provided on the same outer surface of the pre-composite. These pressure pads can be independently temperature-controlled (i.e., heated and / or cooled) or controlled by the temperature controller. The pressure pads are arranged vertically one above the other. It is also possible for the pressure pads themselves to be divided into independently temperature-controlled chambers, which are arranged vertically one above the other and can be independently temperature-controlled or controlled by the temperature controller. This allows the curing rate of the corresponding adhesive components to be adjusted to achieve the most uniform curing possible.

[0070] For example, if the optically clear adhesive is poured into the cavity between the panes from below (inlet opening is at the bottom), the temperature can be set so that it drops from bottom to top (i.e., one pressure pad or chamber of a pressure pad has a lower temperature than the one directly below it). This means that an earlier added portion of the optically clear adhesive, which migrates upwards in the LOCA column through a later added portion of the optically clear adhesive and is thus located in an upper region of the LOCA column, will cure more slowly due to the lower temperature than the later added portion of the optically clear adhesive, which is located in a lower region of the LOCA column, where the temperature is higher, resulting in faster curing.With a suitable adjustment of the temperature profile, a comparatively uniform curing can be achieved, with the entire LOCA column being fully cured at approximately the same time.

[0071] The reverse approach is also possible: if the optically clear adhesive is poured into the cavity between the panes from above (inlet opening is at the top), the temperature can be set so that it drops from top to bottom (i.e. one pressure pad or chamber of a pressure pad always has a higher temperature than the one directly below it). In this way, an earlier added portion of the optically clear adhesive, which migrates downwards in the LOCA column through a later added portion of the optically clear adhesive and is thus located in a lower area of ​​the LOCA column, will cure more slowly due to the lower temperature than the later added portion of the optically clear adhesive, which is located in an upper area of ​​the LOCA column where the temperature is higher, resulting in faster curing.With a suitable adjustment of the temperature profile, a comparatively uniform curing can also be achieved in this case, with the entire LOCA column being fully cured at approximately the same time.

[0072] In general, it is therefore possible for the optically clear adhesive poured into the space between the panes to be heated to different temperatures in different adhesive portions, such that a portion of the adhesive poured in later has a higher temperature than a portion of the adhesive poured in earlier. Embodiments of the method according to the invention have the following features: i) on both outer surfaces of the pre-laminated composite, a plurality of pressure pads are arranged vertically one above the other, which can be temperature-controlled or are temperature-controlled independently of one another in such a way that a portion of the liquid, optically clear adhesive poured into the space between the panes later is heated to a higher temperature than a portion of the liquid, optically clear adhesive poured into the space between the panes earlier, or ii) on both outer surfaces of the pre-laminated composite, at least one pressure pad is divided into chambers arranged vertically one above the other, which can be temperature-controlled or are temperature-controlled independently of one another in such a waytempered so that a portion of the liquid, optically clear adhesive that is later poured into the space between the panes is heated to a higher temperature than a portion of the liquid, optically clear adhesive that was poured into the space between the panes earlier.

[0073] In one embodiment, the often present shrinkage of the liquid, optically clear adhesive during curing is compensated for. Many optically clear adhesives exhibit this type of shrinkage, with their volume decreasing during curing. If the space between the panes is completely filled with the liquid, optically clear adhesive and then cured, this shrinkage can manifest itself in the space between the panes later being incompletely filled with the cured adhesive or in geometric deviations occurring in the laminated pane, particularly with inwardly curved glass panes. This can be compensated for by overfilling the space between the panes with the liquid optically clear adhesive by the amount of shrinkage. As long as the optically clear adhesive is liquid, this exerts pressure and the glass panes, in particular, bend slightly outwards. However, due to the counteracting external pressure, this is not critical.Due to the shrinkage behavior, the volume of the optically clear adhesive decreases, so that in the end a completely filled space between the panes with parallel glass panes is achieved.

[0074] In one embodiment of the method according to the invention, the liquid, optically clear adhesive is poured into the space between the panes in such a quantity that the space between the panes is overfilled, with a portion of the liquid, optically clear adhesive escaping from the pre-laminate outlet opening. The laminated pane produced by the method according to the invention comprises a first glass pane and a second glass pane, which are firmly connected to one another via an intermediate layer, with an electrical functional element advantageously, but not necessarily, located between the glass panes, in particular embedded in the intermediate layer. The intermediate layer is largely, i.e. predominantly or predominantly, formed from an optically clear adhesive. This means that a large portion (i.e. more than 50%, in particular more than 70%) of the volume of the intermediate layer is formed by the optically clear adhesive.

[0075] The intermediate layer contains and consists, in particular, of the cured, optically clear adhesive, optionally the bonding agent used to attach an electrical functional element to the surface of the first glass pane, and the edge seal. The electrical functional element is embedded in the intermediate layer. As already described, an adhesive can be used as the bonding agent. This can also be an optically clear adhesive, in particular the same optically clear adhesive used to fill the cavity between the panes and which then forms the predominant portion of the intermediate layer. In this case, the bonding agent in the finished laminated pane can sometimes no longer be distinguished from the remaining optically clear adhesive.

[0076] The first and second glass panes are preferably made of soda-lime glass, as is common for window panes. In principle, however, other types of glass can also be used alternatively, for example, quartz glass, borosilicate glass, or aluminosilicate glass. The glass panes are preferably transparent. The thickness of the first and second glass panes is preferably between 0.5 mm and 5 mm. The thicknesses of the two glass panes can be selected independently of each other. The first and second glass panes can be clear, i.e., have no tints or colors, or they can be tinted or colored.

[0077] The composite pane preferably contains an integrated electrical functional element, which is preferably a functional film with electrically controllable optical properties. Such functional films are generally constructed as a multilayer film comprising a first carrier film, a first surface electrode, an active layer or layer sequence, a second surface electrode, and a second carrier film, which are arranged flat on top of one another in the specified order. The carrier films are made, for example, from polyethylene terephthalate (PET) and have a thickness of 0.1 mm to 1 mm, preferably 0.1 mm to 0.5 mm. The surface electrodes are formed, for example, as layers based on a metal (in particular silver) or a transparent electrically conductive oxide, in particular indium tin oxide (ITO), with a thickness of 10 nm to 2 pm, preferably 20 nm to 1 pm.The active layer or layer sequence depends on the type of functional film. It exhibits electrically controllable optical properties, which can be controlled by applying a voltage to the surface electrodes.

[0078] The functional film can, in particular, be an SPD film. SPD functional films contain an active layer between the surface electrodes, which contains suspended particles, preferably embedded in a viscous matrix. The absorption of light by the active layer can be modified by applying a voltage to the surface electrodes, which leads to a change in the orientation of the suspended particles. The functional film can also be a film based on liquid crystal technology. Such functional films contain an active layer with liquid crystals. The liquid crystals can be aligned by applying a voltage to the surface electrodes, on which the electrical control of the optical properties is based. The functional film can, for example, be a PDLC film. The active layer contains droplets of liquid crystals in a polymer network.If the liquid crystals are aligned in an electric field, the state is transparent and does not scatter light. If the liquid crystals are not aligned without an electric field, the state is translucent and strongly scatters light. Alternatively, the functional film can be a so-called guest-host film, for example. The active layer contains dichroic dye molecules (guest) dissolved in liquid crystals (host). In the electric field, the liquid crystals are aligned, influencing the orientation of the dye molecules, which leads to a changed transmittance (tint) and a changed color. Experience has shown that guest-host films are particularly sensitive, so the present invention particularly unfolds its advantages in this case. The functional film can also be an electrochromic film.Electrochromic functional films contain an active layer sequence between the surface electrodes (electrochromic layer sequence), which comprises an ion storage layer, an electrolyte layer, and an electrochromic layer arranged one above the other in the specified order. The electrochromic layer actually carries the electrically controllable optical properties. It is an electrochemically active layer whose light transmission depends on the degree of ion incorporation. The ions (e.g., H) + -, Li + , N / a + - or K +Ions are stored in the ion storage layer and made available by it. The electrolyte layer spatially separates the electrochromic layer from the ion storage layer and serves to facilitate the migration of ions. If a direct voltage of suitable polarity is applied to the surface electrodes, ions migrate from the ion storage layer through the electrolyte layer into the electrochromic layer, whereupon the optical properties (color, light transmission) of the electrochromic layer change depending on the extent of the migrated ions. If a direct voltage of opposite polarity is applied to the surface electrodes, the ions migrate back from the electrochromic layer through the electrolyte layer into the ion storage layer, and the optical properties of the electrochromic layer change in the opposite way. If no voltage is applied to the surface electrodes, the current state remains stable.Suitable electrochromic layers contain electrochromic materials, for example, inorganic oxides (such as tungsten oxide or vanadium oxide), complex compounds (such as Prussian blue), or conductive polymers (such as 3,4-polyethylenedioxythiophene (PEDOT) or polyaniline). The electrolyte layer is typically formed as a film of organic or inorganic, electrically insulating material with high ionic conductivity, for example, based on lithium phosphorus oxynitride. The ion storage layer is either permanently transparent (pure ion storage) or exhibits electrochromic behavior opposite to that of the electrochromic layer. An example of a pure ion storage layer is a layer containing a mixed oxide of titanium and cerium. Examples of anodic electrochromic ion storage layer are layers containing iridium oxide or nickel oxide.

[0079] However, the invention can also be implemented with other functional elements, for example with light sources (in particular LEDs, OLEDs or electroluminescent films) or light guide layers, with photovoltaic modules or other electrical modules.

[0080] The first and / or second glass pane can be pre-laminated with additional thermoplastic films, in particular based on PVB, EVA, or TPU, before the composite pane according to the invention is produced. The thermoplastic film can be arranged on the surface of the respective glass pane facing toward the intermediate layer or on the surface facing away from the intermediate layer.

[0081] The laminated pane can be intended to separate an interior space from the exterior environment in an opening in a building or a window opening in a vehicle. The pane which faces the interior space when installed is called the inner pane. The pane which faces the exterior space when installed is called the outer pane. It is irrelevant whether the first or the second glass pane forms the outer pane or inner pane. The two glass panes each have an outer surface and an interior surface and a circumferential side edge running between them. The outer surface is the main surface which is intended to face the exterior environment when installed. The interior surface is the main surface which is intended to face the interior space when installed.The interior surface of the outer pane and the exterior surface of the inner pane face each other and are connected by the intermediate layer.

[0082] The invention also shows the use of the composite pane on buildings or in means of transport for traffic on land, in the air or on water, in particular in motor vehicles, for example as a windscreen, roof window, side window or rear window, in particular in a passenger car or lorry.

[0083] The various embodiments of the invention can be implemented individually or in any combination. In particular, the features mentioned above and explained below can be used not only in the specified combinations, but also in other combinations or on their own, without departing from the scope of the present invention. The above statements in connection with the composite pane apply analogously to the inventive method for producing the same.

[0084] The invention is explained in more detail below using exemplary embodiments, with reference to the accompanying figures. They show, in simplified form and not to scale:

[0085] Figure 1 shows a cross section through a design of a pre-composite for producing a composite pane,

[0086] Figure 2A-2B cross sections through a first embodiment and a second embodiment of the composite pane,

[0087] Figure 3 shows a cross-section through a device with the pre-composite of Figure 1 for producing the composite pane in Figure 2A according to a first embodiment of the method according to the invention at a first time during the production of the composite pane,

[0088] Figure 4 shows a cross-section through the device of Figure 3 at a later second time during the manufacture of the composite pane,

[0089] Figure 5 shows a cross-section through the device of Figure 3 at a later third time during the manufacture of the composite pane,

[0090] Figure 6 is a perspective view of an arrangement of several devices from Figure 3, each with a pre-composite for producing a composite pane,

[0091] Figure 7 shows a cross section through a device with a pre-composite of Figure 1 for producing the composite pane in Figure 2A according to a second embodiment of the method according to the invention at a first time during the production of the composite pane,

[0092] Figure 8 shows a cross-section through the device of Figure 7 at a later second time during the manufacture of the composite pane,

[0093] Figure 9 shows a cross-section through a variant of the device of Figure 7 for producing the composite pane,

[0094] Figure 10 is a flow chart of the process for producing a composite pane.

[0095] Figure 1 shows a cross section through an embodiment of a pre-composite 101 for producing the composite pane 100. Embodiments of the composite pane 100 are shown in Figures 2A and 2B.

[0096] The composite pane 100 comprises a first glass pane 1 and a second glass pane 2, which are connected to one another via an intermediate layer 3. The glass panes 1, 2 are made, for example, from soda-lime glass and have a thickness of 2.1 mm. The intermediate layer 3 has, for example, a thickness of 1 mm. In the embodiment of Figure 2A, the composite pane 100 does not contain an electrical functional element. In the embodiment of Figure 2B, the composite pane 100 is provided, for example, as the roof window of a passenger car, which can be electrically darkened. For this purpose, an electrical functional element 4 is embedded in the intermediate layer 3. The functional element 4 is, for example, a functional film with electrically controllable optical properties, with which the transparency of the composite pane can be electrically controlled.Such a vehicle roof window is typically slightly spherically curved, even though the laminated pane 100 is shown flat for simplicity. It is irrelevant which of the glass panes 1, 2 forms the outer pane or the inner pane of the laminated pane. In the installed position, the outer pane faces the exterior of the vehicle, while the inner pane faces the vehicle interior.

[0097] The intermediate layer 3 is essentially made of an optically clear adhesive 5. In the embodiment of Figure 2B, the functional element 4 is embedded in this optically clear adhesive 5. In addition, the intermediate layer 3 has a circumferential edge seal 6, which is arranged in a circumferential edge region between the glass panes 1, 2 and laterally delimits the layer of optically clear adhesive 5. In the embodiment of Figure 2B, the intermediate layer 3 further comprises an adhesive 7, with which the electrical functional element 4 is attached at specific points to the first glass pane 1. Instead of the adhesive 7 applied at specific points, an adhesive layer could also be used, e.g. a thermoplastic layer, which is produced, for example, by a PVB film with a thickness of 0.38 mm, which bonds the electrical functional element 4 to the first glass pane 1 over the entire surface.

[0098] As schematically shown in Figure 1, during the production of the composite pane 100 from the pre-composite 101, optically clear adhesive 5 in liquid form is introduced into a gap 12 between the two glass panes 1, 2. The hydrostatic pressure of the liquid, optically clear adhesive 5 (liquid column) pushes the two glass panes 1, 2 outwards, which can lead to undesired warping or deformation of the glass panes 1, 2 or even to pane breakage. In Figures 1 and 2, this is illustrated by the arrows pointing away from each other. A detailed description of the pre-composite 101 follows below.

[0099] The composite pane 100 is manufactured using a particularly gentle manufacturing process, as will be described in more detail below using exemplary embodiments. Consider first Figures 3 to 5, which illustrate a first exemplary embodiment of the method according to the invention.

[0100] First, the pre-composite 101 for the laminated pane 100 is provided, as shown in Figure 1. The pre-composite 101 comprises the first glass pane 1 with a first surface

[0101] 1 and a second surface II and the second glass pane 2 with a third surface III and a fourth surface IV. The first glass pane 1 is connected to the second glass pane 2 via a circumferential edge seal 6 provided with at least one pre-bonded inlet opening 8 and at least one pre-bonded outlet opening 9. The first surface I of the first glass pane 1 and the fourth surface IV of the second glass pane

[0102] 2 face away from each other and form the two outer surfaces 13 of the pre-laminate 101, while the second surface II and the third surface III face each other and form the two inner surfaces 14 of the pre-laminate 101. A space 12 is formed between the two glass panes 1, 2 and the edge seal 6. A supply line 10 is connected to the pre-laminate inlet opening 8, and a vent line 11 is connected to the pre-laminate outlet opening 9.

[0103] The pre-composite assembly 101 can be produced, for example, by connecting the first glass pane 1 to the second glass pane 2 via the circumferential edge seal 7. For the embodiment shown in Figure 2, the electrical functional element 4 is first attached to a surface of the first glass pane 1 using the adhesive 7 applied at specific points. The adhesive dots can, for example, be distributed in a circumferential edge region of the functional element 4. When the two glass panes 1, 2 are connected, the surface of the first glass pane 1 which is provided with the functional element 4 faces the second glass pane 2. This forms the space 12 (cavity) between the panes, which is delimited by the glass panes 1, 2 and the edge seal 6. The functional element 4 is arranged in the space 12 between the panes.The edge seal 6 is then provided with at least one pre-composite inlet opening 8 and at least one pre-composite outlet opening 9. For this purpose, for example, cannulas can be driven through the edge seal 6 or the edge seal 6 can be provided with valves. The pre-composite inlet opening 8 serves to fill the space 12 between the panes with optically clear adhesive 5 in liquid form. The pre-composite outlet opening 9 serves to vent the space 12 between the panes during the filling process. For the production of the composite pane 100, a device 103 is provided (see Figures 3 to 5), which has a frame 15 in which flexible pressure pads 17 are arranged such that they can accommodate the pre-composite 101 between them. In the present exemplary embodiment, for example, two flexible pressure pads 17 are provided.The flexible pressure cushions 17 each have a cushion cover 18 which essentially consists of a flexible material, here for example of a polymer film (e.g. made of PVC), although other materials are also conceivable, for example textiles. The flexible cushion cover 18 defines a cushion cavity 19 which can be reversibly filled with a gaseous or aqueous fluid 24, i.e. the cushion cavity 19 can also be emptied again. For this purpose, the cushion cover 18 has, each opening into the cushion cavity 19, a pressure cushion inlet opening 20 for supplying fluid 24 and a pressure cushion outlet opening 20' for venting during the filling of the cushion cavity 19 with fluid 24 and during the emptying of the cushion cavity 19 by removing fluid 24 from the cushion cavity 19.In the figures, the pressure pad inlet opening 20 and the pressure pad outlet opening 20' are shown for the sake of simplicity as a combined pressure pad inlet opening / pressure pad outlet opening 20, 20', although it is understood that the pressure pad inlet opening 20 and the pressure pad outlet opening 20' can also be located separately from one another at different locations on the pressure pad 17. In the exemplary embodiments described here, a liquid fluid 24 is filled into the pressure pads 17. The fluid 24 can, in particular, be guided in a closed circuit, wherein it can be fed from a reservoir (not shown) to the pressure pads 17 and transported from the pressure pads 17 back into the reservoir, for example by means of a circulating pump.

[0104] The pre-laminate assembly 101 is arranged in a vertical arrangement of the two glass panes 1, 2 between the two pressure pads 17 and secured in the frame 15 by means of fixing means, which is not shown in detail in the figures. The pressure pads 17 are deflated when the pre-laminate assembly 101 is inserted between the two pressure pads 17, so that no pressure is exerted on the glass panes 1, 2 of the pre-laminate assembly 101. The pressure pads 17 are located on both sides of the pre-laminate assembly 101.

[0105] The pressure pads 17 can each be filled with 24 fluid, wherein the pressure pads 17 are designed here, for example, such that when fully filled, they essentially have a cuboid shape (see Figure 5). When fully filled, the pressure pads 17 thus each have two opposing main surfaces 21, which are connected to one another by a circumferential side edge surface 22 running between them. One main surface 21 of a respective pressure pad 17 faces the pre-assembly 101 and serves as a pressure surface 23 for surface contact against the adjacent outer surface 13. The other main surface 21 of a respective pressure pad 17 faces a frame wall 16 and serves for surface contact against the frame wall 16.

[0106] The pre-assembly 101 is arranged between the two pressure pads 17 in such a way that the pressure surfaces 23 of the two pressure pads 17 can come into contact with the respective adjacent outer surface 13 of the pre-assembly 101. The initially slack pressure surfaces 23, which do not or only randomly contact the outer surfaces 13, successively contact the outer surfaces 13 as the pressure pads 17 are increasingly filled. Thus, the pressure surfaces 23 are brought into contact with the outer surfaces 13, in which fluid 24 is absorbed in the pressure pad 17. As the filling increases, each pressure pad 17 is clamped, as it were, between the outer surface 13 of the pre-assembly 101 and the frame wall 16 by the hydrostatic pressure of the liquid column, so that the hydrostatic pressure of the fluid 24 is transferred to the outer surface 13 as external pressure via the pressure surface 23 contacting the outer surface 13.The internal pressure acting on the two glass panes 1, 2 due to the hydrostatic pressure of the liquid, optically clear adhesive in the cavity 12 between the panes can thus be counteracted by an external pressure acting on both sides of the pre-laminate 101. As shown in Figure 5, the pressure surfaces 23 of the pressure pads 17 are in full contact with the outer surfaces 13 when the pressure pads 17 are completely filled with fluid 24. The pressure pads 17 or the pressure surfaces 23 are dimensioned such that the outer surfaces 13 are completely covered. In the present example, the size and shape of the pressure surfaces 23 are the same as the size and shape of the outer surfaces 13.

[0107] As shown in Figures 3 to 5, the pre-composite 101 is received in the device 103 such that the glass panes 1, 2 are aligned substantially vertically. The pre-composite inlet opening 8 points downwards, and the pre-composite outlet opening 9 points upwards. The pre-composite inlet opening 8 is connected to the supply line 10, which is intended to supply the optically clear adhesive 5 in liquid form from a reservoir (not shown) to the pre-composite inlet opening 8. The supply line 10 is, for example, a plastic hose. The pre-composite outlet opening 9 is connected to the vent line 11. The vent line 11 can, for example, also be a plastic hose or a pipe made of metal or plastic. In this process, the pre-composite 101, which does not yet contain any optically clear adhesive 5, is arranged between the pressure pads 17 (not filled with fluid 24).Subsequently, the space between the panes 12 is filled with optically clear adhesive 5 and, at the same time, the pressure pads 17 are filled with fluid 24. As illustrated in particular in Figures 3 and 4, while the space between the panes 12 is being filled with the optically clear adhesive 5, fluid 24 is simultaneously introduced into the pressure pads 17. A fluid is preferably used that has approximately the same density as the optically clear adhesive 5. The fluid 24 can be water, for example. The filling speeds are coordinated such that the surface of the optically clear adhesive 5 already filled into the space between the panes 12 and the surfaces of the fluid 24 in the pressure pads 17 are essentially at the same level at all times.The more optically clear adhesive s is poured into the cavity 12 between the panes, the higher the optically clear adhesive s rises in the cavity 12 between the panes and the more fluid 24 is poured into the pressure pads 17. The respective levels 25 are the same. Figures 3 and 4 show two points in time, with Figure 4 corresponding to the state at a later point in time, where the level 25 is already higher.

[0108] The internal pressure acting on the inner surfaces 14 of the pre-laminate 101, caused by the hydrostatic pressure of the optically clear adhesive 5 in the cavity 12 between the panes, and the external pressure acting on the outer surfaces 13 of the pre-laminate 101 are always balanced during this process. Thus, while the cavity 12 is being filled, there is effectively (in particular at least approximately) no pressure acting on the glass panes 1, 2. If the optically clear adhesive 5 were to be poured into the cavity 12 between the panes in an air atmosphere, the liquid column of the optically clear adhesive 5 would exert internal pressure, which could deform or even break the glass panes 1, 2, or which could also damage the edge seal 6. The optically clear adhesive 5 is, for example, a 2-component polyurethane adhesive.

[0109] As shown in Figure 5, the pressure surfaces 23 of the pressure pads 17 lie completely (flat) against the outer surfaces 13 when the space between the panes 12 is completely filled with optically clear adhesive 5 and the pressure pads 17 are correspondingly completely filled with fluid 24. It is understood that complete filling of the pressure pads 17 is not necessary if the pressure pads 17 are dimensioned so large that the pressure surfaces 23 lie completely against the outer surfaces 13 even when partially filled (i.e. with 100% surface coverage). As soon as the space between the panes 12 is completely filled with the optically clear adhesive 5, the optically clear adhesive 5 is cured. Depending on the adhesive 5 used, this can be done, for example, thermally, by UV radiation or the chemical reaction of a two-component adhesive. The curing of the adhesive 5 forms the composite pane 100 from the pre-composite 101.The pre-composite 101 remains in the device 103 during curing, and external pressure continues to be exerted on the outer surfaces 13 as long as the optically clear adhesive 5 has not yet cured and hydrostatic pressure is still exerted on the inner surfaces 14. Once the optically clear adhesive 5 has cured, there is no longer any internal pressure on the inner surfaces 14, and the composite disc 100 can be removed from the device 103. The pre-composite inlet opening 8 and the pre-composite outlet opening 9 are closed, for example, by withdrawing the cannulas or removing the valves.

[0110] For the sake of simplicity, Figures 3 to 5 show the pre-composite 101 from Figure 1 for producing the composite pane 100 of Figure 2A, wherein the composite pane of Figure 2B can be produced by the same method.

[0111] Figure 6 illustrates an arrangement in which several devices 103 are provided in a row next to one another, with which several composite panes 100 can be produced simultaneously. The method according to the invention is thus easily scalable in terms of quantity.

[0112] In the following, a further embodiment of the method according to the invention is illustrated with reference to Figures 7 and 8, wherein only the differences from the embodiment of Figures 3 to 5 are explained and otherwise reference is made to the explanations therein.

[0113] In the exemplary embodiment of Figures 3 to 5, the pre-composite 101 is arranged between the pressure pads 17 that are not filled with fluid 24. The space between the panes 12 is then filled with optically clear adhesive 5 and, at the same time, the pressure pads 17 are filled with fluid 24. In contrast, in this process, the pressure pads 17 are already filled with fluid 24, preferably completely. While the space between the panes 12 is filled with the optically clear adhesive 5, the pre-composite 101 is simultaneously inserted between the fluid-filled pressure pads 17. The filling speed and the insertion movement are coordinated such that the surface of the optically clear adhesive 5 already filled into the space between the panes 12 and the surfaces of the fluid 24 in the pressure pads 17 are essentially at the same height at all times.The more optically clear adhesive 5 is poured into the cavity 12 between the panes, the higher the optically clear adhesive 5 rises in the cavity 12 between the panes and the deeper the pre-composite 101 is inserted between the two pressure pads 17. The respective levels 25 are the same. Figures 7 and 8 show two points in time, with Figure 8 corresponding to the state at a later point in time, where the level 25 is already higher and corresponds to a complete filling of the cavity 12 between the panes with optically clear adhesive 5.

[0114] The internal pressure acting on the inner surfaces 14 of the pre-laminated composite 101, caused by the hydrostatic pressure of the optically clear adhesive 5 in the cavity 12 between the panes, and the external pressure acting on the outer surfaces 13 of the pre-laminated composite 101 always remain balanced in this process as well. Thus, effectively (in particular, at least approximately) no pressure acts on the glass panes 1, 2 during the filling of the cavity 12 between the panes.

[0115] Once the gap 12 is completely filled with the optically clear adhesive 5, the optically clear adhesive 5 is cured, with the pre-composite 101 remaining in the device 103 and external pressure being continuously exerted on the outer surfaces 13 as long as the optically clear adhesive 5 has not yet cured and a hydrostatic pressure is exerted on the inner surfaces 14. The composite pane 100 can then be removed from the device 103, and the pre-composite inlet opening 8 and the pre-composite outlet opening 9 are closed.

[0116] As already explained, a constant difference between the levels of fluid 24 and optically clear adhesive 5 can also be provided in the various process controls, for example in order to compensate for different densities of optically clear adhesive 5 and fluid 24 or other differences between internal and external pressure.

[0117] Figure 9 illustrates a variant of Figures 7 and 8, in which the fluid-filled pressure pads 17 each have different chambers 26, which can be temperature-controlled independently of one another, so that the temperature of each chamber 26 can be set independently of the other chambers 26. If an optically clear adhesive 5 is used that begins to cure immediately (for example, a two-component adhesive in which the chemical reaction begins immediately upon filling), the curing occurs unevenly: the earlier a certain proportion of optically clear adhesive 5 is filled, the sooner it cures. However, the curing speed is typically temperature-dependent. The further development shown with the chambers 26 allows the curing behavior to be homogenized.

[0118] The temperature of the chambers 26 rises from top to bottom. The first portion of optically clear adhesive s to be added is always located in the upper part of the liquid column. There the temperature is low and curing takes place slowly. The later additional portions of optically clear adhesive 5 are added, the further the pre-composite 101 is inserted and the deeper they are therefore positioned. These portions are therefore cured in chambers located further down, where the temperature is higher and the curing rate correspondingly higher. They have less time available for curing, but curing is accelerated by the higher temperature. The last portion of optically clear adhesive 5 is located in the lowest chamber with the highest temperature and therefore cures the fastest.

[0119] By using a suitable temperature profile, it is possible to ensure that the entire optically clear adhesive 5 reaches its full degree of curing at approximately the same time. This is advantageous with regard to the optical quality of the composite pane 100 and the mechanical stresses during production.

[0120] Although four chambers 26 are shown in Figure 9, the number of chambers 26 can be smaller or, preferably, larger. The more chambers 26 are formed, the more finely the temperature profile can be adjusted. A high number of chambers 26 ideally allows for a quasi-continuous temperature profile to be created, which is ideal for homogenizing the curing process.

[0121] Figure 10 illustrates the method according to the invention using a flowchart. Steps a) to c) refer to:

[0122] Step a) Providing a pre-composite assembly 101 comprising a first glass pane 1 having a first surface I and a second surface II and a second glass pane 2 having a third surface III and a fourth surface IV, wherein the first glass pane 1 is connected to the second glass pane 2 via a circumferential edge seal 6 provided with at least one pre-composite inlet opening 8 and at least one pre-composite outlet opening 9, wherein the first surface I and the fourth surface IV face away from each other and form the outer surfaces 13 of the pre-composite assembly 101, and the second surface II and the third surface III face each other and form the inner surfaces 14 of the pre-composite assembly, wherein a space 12 between the panes is formed between the two glass panes 1, 2 and the edge seal 6,

[0123] Step b)

[0124] Pouring a liquid, optically clear adhesive 5 into the space between the panes 12, wherein during the pouring, a hydrostatic pressure of the liquid, optically clear adhesive 5 acting as internal pressure on the inner surfaces 14 is counteracted by an external pressure acting on the outer surfaces 13, wherein the external pressure is exerted by pressure surfaces 23 of pressure pads 17, which lie flat against the outer surfaces 13, and wherein the external pressure is based on the hydrostatic pressure of fluid 24 in the pressure pads 17,

[0125] Step c)

[0126] Curing of the liquid, optically clear adhesive 5 while maintaining the external pressure on the outer surfaces 13, whereby the composite pane 100 is formed.

[0127] From the above, it can be seen that the invention provides an improved method for producing composite panes, by which composite panes can be produced with high optical quality and low waste due to comparatively low mechanical stress. This applies particularly to composite panes with integrated electrical functional elements. The method can be implemented in the industrial series production of composite panes in conventional production facilities, so that composite panes with high optical quality and low waste can be produced in large numbers simply, cost-effectively, and reliably. Reference symbols:

[0128] 1 first glass pane

[0129] 2 second glass pane

[0130] 3 Intermediate layer

[0131] 4 electrical functional element

[0132] 5 optically clear adhesive

[0133] 6 Edge sealing

[0134] 7 Adhesives

[0135] 8 Pre-composite inlet opening

[0136] 9 Pre-composite outlet opening

[0137] 10 Supply line

[0138] 11 Ventilation line

[0139] 12 space between panes

[0140] 13 Exterior area

[0141] 14 inner surface

[0142] 15 frame

[0143] 16 frame wall

[0144] 17 pressure pads

[0145] 18 pillowcases

[0146] 19 Pillow cavity

[0147] 20 Pressure pad inlet opening

[0148] 20' pressure pad outlet opening

[0149] 21 Main area

[0150] 22 side edge surface

[0151] 23 printing area

[0152] 24 Fluid

[0153] 25 levels

[0154] 26 Chamber

[0155] 100 composite panes

[0156] 101 Pre-composite

[0157] 103 Device

Claims

Claims 1 . A method for producing a composite pane (100), comprising: Providing a pre-composite assembly (101) comprising a first glass pane (1) having a first surface (I) and a second surface (II), and a second glass pane (2) having a third surface (III) and a fourth surface (IV), wherein the first glass pane (1) is connected to the second glass pane (2) via a circumferential edge seal (6) provided with at least one pre-composite inlet opening (8) and at least one pre-composite outlet opening (9), wherein the first surface (I) and the fourth surface (IV) face away from one another and form the outer surfaces (13) of the pre-composite assembly (101), and the second surface (II) and the third surface (III) face towards one another and form the inner surfaces (14) of the pre-composite assembly, wherein a space (12) between the two glass panes (1, 2) and the edge seal (6) is formed, Filling a liquid, optically clear adhesive (5) into the space between the panes (12), wherein during the filling process, a hydrostatic pressure of the liquid, optically clear adhesive (5) acting as internal pressure on the inner surfaces (14) is counteracted by an external pressure acting on the outer surfaces (13), wherein the external pressure is exerted by pressure surfaces (23) of pressure pads (17) which lie flat against the outer surfaces (13), and wherein the external pressure is based on the hydrostatic pressure of fluid (24) in the pressure pads (17), Curing the liquid, optically clear adhesive (5) while maintaining the external pressure on the outer surfaces (13), whereby the composite pane (100) is formed.

2. Method for producing a composite pane (100) according to claim 1, in which the pre-composite (101) is arranged with a substantially vertical arrangement of the two glass panes (1, 2) between the pressure pads (17), the liquid, optically clear adhesive (5) being filled into the space between the panes (12) and, at the same time, fluid (24) being filled into the pressure pads (17).

3. A method for producing a composite pane (100) according to claim 2, wherein the liquid, optically clear adhesive (5) is filled into the space between the panes (12) and the fluid (24) is filled into the pressure pads (17) such that a surface of the liquid, optically clear adhesive (5) and respective surfaces of the fluid (24) in the pressure pads (17) are at all times substantially at the same height or have a constant distance in the direction of gravity at all times.

4. A method for producing a composite pane (100) according to claim 1, wherein the liquid, optically clear adhesive (5) is filled into the space between the panes (12) and at the same time the pre-composite (101) is inserted in a substantially vertical arrangement of the two glass panes (1, 2) between the pressure pads (17) which are at least partially filled with fluid (24).

5. A method for producing a composite pane (100) according to claim 4, wherein the pre-composite (101) is inserted between the pressure pads (17) during the filling of the liquid, optically clear adhesive (5) such that a surface of the liquid, optically clear adhesive (5) and respective surfaces of the fluid (14) in the pressure pads (17) are at all times substantially at the same height or have a constant distance in the direction of gravity at all times.

6. A method for producing a composite pane according to one of claims 1 to 5, wherein the internal pressure acting on the inner surfaces (14) is substantially compensated by the external pressure acting on the outer surfaces (13).

7. A method for producing a composite pane (100) according to one of claims 1 to 6, wherein, when the space between the panes (12) is completely filled with optically clear adhesive (5), the pressure surfaces (23) of the pressure pads (17) lie fully against the outer surfaces (13).

8. A method for producing a composite pane (100) according to one of claims 1 to 7, wherein, when completely filled with fluid (24), the pressure pads (17) each have a substantially cuboid shape, wherein main surfaces (21) of the pressure pads (17) opposite the outer surfaces (13) are pressure surfaces (23) of the pressure pads (17).

9. A method for producing a composite pane (100) according to any one of claims 1 to 8, wherein a density of the liquid, optically clear adhesive (5) corresponds to a density of the fluid (24).

10. A method for producing a composite pane (100) according to one of claims 1 to 9, in which the liquid, optically clear adhesive (5) is applied via a The pre-composite inlet opening (8) located between the panes (12) is filled into the pane space (12).

11. A method for producing a composite pane (100) according to one of claims 1 to 10, in which i) on both outer surfaces (13) of the pre-composite (101) a plurality of pressure pads (17) are arranged vertically one above the other, which are independently temperature-controlled such that a portion of the liquid, optically clear adhesive (5) which is later poured into the space between the panes (12) is heated to a higher temperature than a portion of the liquid, optically clear adhesive (5) which is previously poured into the space between the panes (12), or ii) on both outer surfaces (13) of the pre-composite (101) at least one pressure pad (17) is divided into chambers (26) arranged vertically one above the other, which are independently temperature-controlled such that a portion of the liquid, optically clear adhesive (5) which is later poured into the space between the panes (12) is heated to a higher temperature than a portion of the liquid,optically clear adhesive (5)., 12. A method for producing a composite pane (100) according to one of claims 1 to 11, wherein the liquid, optically clear adhesive (5) is filled into the space between the panes (12) in such a quantity that the space between the panes (12) is overfilled, a portion of the liquid, optically clear adhesive (5) exiting from the pre-composite outlet opening (9).

13. A method for producing a composite pane according to one of claims 1 to 12, in which an electrical functional element (4), for example a functional film with electrically controllable optical properties, in particular an SPD film, a film based on liquid crystal technology or an electrochromic film, a light source or a light guide or a photovoltaic module, is embedded in the optically clear adhesive (5).

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